Pictorials of playmates and other models can be found on the app, which has emerged from months of testing, but there's no nudity.

Apple's content guidelines prohibit pornographic material, but that doesn't prevent the subscription-based Playboy app from being provocative, says Josh Schollmeyer, Playboy's Director of Digital Content. "It forces us to use our imagination to be a little bit more creative," he says. "I tell all my photographers every picture has to be one of three things. It has to be romantic, whimsical or sexy."

Users can download the app free from Apple's App store, but to view the latest content they will need to purchase a monthly subscription ($1.99 per month or $19.99 for the year).

Each month, new exclusive content about The Good Life (travel, food, drink, cars, gear, style) will augment long-form interviews and articles. This month's entries include 20 questions with Girls creator/actress Lena Dunham and an interview with music industry mogul Clive Davis, an opinion piece and a short story. "We still want to give a taste of what appears in the magazine," he says. "We try to make it very medium-friendly. If you go in and look at the Clive Davis interview, we have purposefully made it as easy on the eyes as possible to read 5,000 words on this small of a device."

And of course, there's the pictorials including Playmate Redux, featuring 2001 Playmate of the Year Brande Roderick; God Given Gorgeous, in which photographers - in this case Michael Bernard, who has shot many Victoria's Secret ads -- chose models that represent "a new standard of beauty," Schollmeyer says.

The Miss Social pictorial features the winner of a monthly online social media contest. Soon to be added: Me In My Place -- previously a feature in Esquire, which will now be exclusive to Playboy - a regular pictorial of a celebrity in her home from photographer Michael Edwards.

"The playmates give (the app) a star quality, Me In My Place will give it a celebrity quality," Schollmeyer says. "There's an art quality to God Given Gorgeous and a girl next door quality to Miss Social."

With each subject area, whether it's food, drink, politics or models, "we try to find a very distinctive Playboy take," he says, "and this is how it is manifesting itself on the phone."

For now, the actual Playboy magazine remains available in digital form via Web apps such as Zinio. Within The Vault feature on the iPhone app, users can purchase content from previous months for $1.99 per download.

Playboy's iPhone app will likely migrate to Android devices and tablets, Schollmeyer says. "What you are seeing on the iPhone is really going to be a pilot program for what we do on the tablet, hopefully within the next year or so," he says.

The migration to digital makes sense for magazines because half of all U.S. adults have smart phones now and 205 million will have them by 2016, research firm Forrester estimates. And tablets are on the same adoption curve, with about 34 million owning tablets now and 113 million tablet owners expected by 2016.

Magazine and newspapers are "looking at their store of content and trying to figure out how many different ways can they use it to squeeze advertising revenue or squeeze impressions out of (it)," says mobile strategy analyst Chris Silva of The Altimeter Group.

As publishers attempt to define and fine-tune their digital strategy, "folks are throwing stuff at the wall and seeing what sticks," he says.

If Playboy's non-nude strategy is successful on the iPhone it could carry over to other smart phones and tablets, Silva says. "Just because the (content) controls aren't there on Android, I wouldn't expect them to go more risqué."

Either way, the move is likely to appeal to younger readers. "They'd rather consume the content digitally on their device than on their couch in paper form," Silva says. "The way people are consuming and buying their media has totally changed."